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Related Paty Transactions (Transactions Between Emera and Associated Parties) (Details) - CAD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
NSP Maritime Link Inc. [Member] | Regulated fuel for generation and purchased power [Member] | Regulated [Member] |  |
Related Party Transaction [Line Items] |  |
Related Party Transaction, Purchases from Related Party | $ 97 |
Maritimes and Northeast Pipline [Member] | Natural gas transportation capacity [Member] |  |
Related Party Transaction [Line Items] |  |
Revenue from Related Parties | $ 29 | $ 28

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- Definition Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07.1(c)) -URI http://asc.fasb.org/extlink&oid=6488393&loc=d3e606610-122999 + Details
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